It has long been recognized by those skilled in the art that hand-held chain saws are highly desirable and convenient for cutting and trimming a variety of objects such as trees, limbs, logs, and the like. Of course, it is well-recognized that while the saw is held by the hands of the user, its operational range is limited, largely because of the length of the saw. Accordingly, others have previously suggested various mechanical and electrical means for extending the reach of a chain saw, without requiring substantial modifications to the saw's original design or configuration.
For example, U.S. Pat. No. 3,731,380 issued May 8, 1973 discloses an extension pole for a chain saw which releasably engages a chain saw handle. A manually operable throttle control comprising an operating line extending longitudinally along the pole engages the saw throttle trigger for speed control. The pole mounting means releasably engages the handle of the saw.
U.S. Pat. No. 3,731,382 issued May 8, 1973 discloses an extensible chain saw insert that is adapted to be interposed between a chain saw motor unit and the cutting chain apparatus for extending the saw to different selected lengths. In this manner, a standing operator may cut and trim tree branches of substantial thickness that may be substantially elevated above ground.
U.S. Pat. No. 3,949,817 issued Apr. 13, 1976 discloses a chain saw extender for extending the reach of a portable chain saw for cutting tree limbs and branches which would otherwise be inaccessible to the operator. An elongated post which can be held in the hands is connected to the chain saw. A pivotable lever attached to the front end of the post contacts and depresses the power trigger on the chain saw. A finger operated control trigger is located at the rear end of the post, and means are provided for connecting the pivotable lever and the control trigger for manual speed control.
U.S. Pat. No. 4,359,822 issued Nov. 23, 1982 shows another power chain saw handle attachment adapting a chain saw for use in cutting underbrush, weeds, and the like. The curved handle attachment is detachably, pivotally fixed on the body of the power chain saw, and positions the cutting bar in a horizontal position instead of the conventional vertical position when the chain saw is being operated in a normal manner. The handle attachment is adjustable to accommodate users of different height. The handle of the chain saw attachment is provided with an adjustable position hand grip and throttle control assembly.
U.S. Pat. No. 4,638,562 issued Jan. 27, 1987 provides extension handles for electrical and gasoline-operated hedge type trimmers. Extension handle mounting assemblies can be securely clamped to the motor housing of the trimmers to provide one or more secure support points interconnecting the extension handles.
U.S. Pat. No. 4,999,917 issued Mar. 19, 1991 discloses a chain saw extension structure enabling a chain saw to functionally elongate and thus reach remote elevations. A drive transmitting extension structure fitted to a chain saw interconnects the saw drive motor and cutting head.
U.S. Pat. No. 5,884,403 issued Mar. 23, 1999 discloses an electric tree trimming apparatus including an elongate, telescoping, tubular handle having a bracket provided on its upper end that releasably mounts an electric chain saw. A coiled extension cord accommodated within the handle has a socket for releasable attachment to the saw's electric plug, with a second plug at its opposite end for connection to a power source. A remote trigger switch mounted on the handle is electrically coupled to the extension cord to remote power the saw.
U.S. Pat. No. 7,152,328 issued Dec. 26, 2006 discloses an electric pole saw with a powerhead mounting assembly comprising interlocking bracket halves molded to conform to the shape of the saw. Single-point fastening means enable fast and easy assembly of the bracket without tools.